Gravity of Jupiter and Venus elongates Earth’s orbit every 405,000 years – study

Amazing what can be gleaned from a 1,700 feet long rock core.
H/T Ian Wilson

Every 405,000 years, gravitational tugs from Jupiter and Venus slightly elongate Earth’s orbit, an amazingly consistent pattern that has influenced our planet’s climate for at least 215 million years and allows scientists to more precisely date geological events like the spread of dinosaurs, according to a Rutgers-led study.

The findings are published online today in the Proceedings of the National Academy of Sciences, reports ScienceDaily.

“It’s an astonishing result because this long cycle, which had been predicted from planetary motions through about 50 million years ago, has been confirmed through at least 215 million years ago,” said lead author Dennis V. Kent, a Board of Governors professor in the Department of Earth and Planetary Sciences at Rutgers University-New Brunswick.

“Scientists can now link changes in the climate, environment, dinosaurs, mammals and fossils around the world to this 405,000-year cycle in a very precise way.”

The scientists linked reversals in the Earth’s magnetic field — when compasses point south instead of north and vice versa — to sediments with and without zircons (minerals with uranium that allow radioactive dating) as well as to climate cycles.

“The climate cycles are directly related to how the Earth orbits the sun and slight variations in sunlight reaching Earth lead to climate and ecological changes,” said Kent, who studies Earth’s magnetic field. “The Earth’s orbit changes from close to perfectly circular to about 5 percent elongated especially every 405,000 years.”

The scientists studied the long-term record of reversals in the Earth’s magnetic field in sediments in the Newark basin, a prehistoric lake that spanned most of New Jersey, and in sediments with volcanic detritus including zircons in the Chinle Formation in Petrified Forest National Park in Arizona.

They collected a core of rock from the Triassic Period, some 202 million to 253 million years ago. The core is 2.5 inches in diameter and about 1,700 feet long, Kent said.

The results showed that the 405,000-year cycle is the most regular astronomical pattern linked to the Earth’s annual turn around the sun, he said.

Good to see some recognition that the long eccentricity cycle is the strongest in W/m2 and also the most stable “Milankovitch” cycle. (Yet has seemingly no spectral power in the Pleistocene) Difficult to understand how the model of this cycle breaks down at 50 million years. Time to tune the model to reality.

Kent and Olsen say that each 405,000 years, when orbital eccentricity is at its peak, seasonal variations attributable to shorter cycles will develop into extra intense; summers are hotter and winters colder; dry instances drier, moist instances wetter. The reverse might be true 202,500 years later, when the orbit is at its most round.

Now, that’s an interesting graph.
Good. Now other studies are confirming, that man is the problem, he measures, whereas a monkey uses a stick to gather ants to eat. But? Why the breakover date? Did we pass a star, enter a dust cloud? Raises more questions. Good.

The orbital periods of Jupiter and Venus with respect to the Earth do not just affect the oblateness of the Earth’s orbit, they have also affected the current precession rates of the line-of-nodes and the line-of-apse of the lunar orbit. This means that the orbital periods of Venus and Jupiter may indirectly affect the Earth climate system via the influence of the lunar tides.

We know that the strongest planetary tidal forces acting on the lunar orbit come from the planets Venus and Jupiter. In addition, we know that, over the last 4.6 billion years, the Moon has slowly receded from the Earth. During the course of this lunar recession, there have been times when the orbital periods of Venus and Jupiter have been in resonance(s) with the precession rate for the line-of-nodes and the line-of-apse of the lunar orbit ( Cuk 2007). When these resonances have occurred, they would have greatly amplified the effects of the planetary tidal forces upon the lunar orbit ( Cuk 2007).

Hence, the observed synchronization between the precession rates for the line-of-nodes and line-of-apse of the lunar orbit and the orbital periods of Venus, Earth, and Jupiter, could simply be a cumulative fossil record left behind by these historical resonances.

This could explain why:

(1/(2DY) + (1/(9FMC) = 1/SEV

where DY = Draconic year = 0.948978 sidereal years
FMC = Full Moon Cycle = 1.127385 sidereal years
and SEV = The synodic period of Venus and the Earth = 1.598660 sidereal years.

[N.B. The length of the Draconic year is set by the precession rate of the lunar line-of-nodes compared to the orbital motion of the Earth about the Sun.]
[N.B. The length of the Full Moon Cycle is set by the precession rate of the lunar line-of-apse compared to the orbital motion of the Earth about the Sun.]
[N.B. The synodic period of Venus and the Earth is the time required for the Earth and Venus to realign in their orbits about the Sun.]

Similarly,

3/(SEV) – 2/(SEJ) = 1/9.055081 – 1/20.292924 – 1/62.006158 = 1/H

where SEV = The synodic period of Venus and the Earth = 1.598660 sidereal years.
________SEJ = The synodic period of Jupiter and the Earth = 1.092066 sidereal years.
__________H = The length of the Hale sunspot cycle = 22.2 sidereal years

The trouble I have (which I am sure is shared by many at the Tallbloke Workshop) is that the argument that I have given above is eminently reasonable, yet it is almost totally ignored by both the alarmist main-stream climate community and even the so-called skeptics at WUWT.

This is particularly true since Nickolay Sidorenkov and I have meticulously demonstrated the existence of these connections in our two papers: